Actuator Stem Guide Apparatus Prevents Diaphragm Housing Contact
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In fluid valve actuators, the movement of springs under load can cause the diaphragm plate to engage the actuator housing, leading to friction, damage, and reduced effective diaphragm area, which in turn reduces the torque provided to the flow control member, resulting in decreased valve performance.
Innovation Solution
An actuator stem guide apparatus is introduced, comprising a housing with a low-friction material bearing surface to guide the actuator stem, preventing it from contacting the actuator housing and limiting translational movement, thus maintaining the diaphragm's integrity and reducing friction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the actuator stem is allowed to move or tilt laterally to enable lever rotation, then the valve can achieve proper rotational displacement, but the diaphragm plate may engage the actuator housing causing friction and damage
Solution Approach 1:
A guide apparatus is introduced as an intermediary component between the actuator stem and the actuator housing. This guide apparatus includes a guide surface that directs the actuator stem's lateral movement, ensuring it follows a controlled path that enables lever rotation while preventing the diaphragm plate from contacting the housing inner surface.
Solution Approach 2:
The guide apparatus modifies the movement parameters of the actuator stem by providing a constrained guide surface. This changes the stem's movement from uncontrolled lateral displacement to a controlled motion along a specific trajectory, allowing lever rotation while maintaining sufficient clearance between the diaphragm plate and housing.
2Strength
If springs are allowed to translate within the housing due to side load forces, then the actuator can accommodate spring compression, but the diaphragm plate may contact the housing creating friction and reducing effective diaphragm area
Solution Approach 1:
The guide apparatus serves as a mediator that manages the interaction between the compressed springs and the diaphragm plate. By providing a controlled guide surface for the actuator stem, it prevents the stem from tilting excessively during spring compression, thereby maintaining the diaphragm plate's position and preserving its effective area.
3Productivity
If the actuator stem moves laterally to convert rectilinear displacement to rotational displacement, then the lever can rotate the valve shaft, but friction is generated that can crimp or deform the diaphragm
Solution Approach 1:
The guide apparatus acts as an intermediary that facilitates the conversion of rectilinear to rotational displacement while minimizing harmful friction. The guide surface provides a controlled path for stem movement, reducing uncontrolled lateral rubbing that would otherwise cause diaphragm crimping or deformation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The actuator stem guide apparatus effectively prevents diaphragm damage and maintains the diaphragm's effective area, enhancing the torque provided to the flow control member and improving the overall performance of the fluid control valve by reducing friction and ensuring proper sealing.
Implementation Method 1
at least a portion of the actuator stem guide apparatus is composed of a low friction material such as, for example, Delrin, Polytetrafluoroethylene (PTFE), Ultra High Molecular Weight Polyethylene (UHMWPE), etc.
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
Actuator stem guide apparatus for use with fluid valve actuators are described. An example actuator stem guide apparatus includes a base having an opening ( 310 ) to allow an actuator stem ( 230 ) of the fluid valve actuator to tilt or lean within the base to enable a lever of the fluid valve actuator to rotate and a guide receiving area adjacent the opening of the base. A guide ( 304 ) is coupled to the guide receiving area and the guide has a bearing surface ( 316 ) to slidably engage the actuator stem to limit lateral movement of a diaphragm assembly relative to a longitudinal axis of the opening to prevent the diaphragm assembly from engaging an inner surface of an actuator housing as the actuator stem moves between a first position and a second position.